A fuel cell assembly comprising an electrostrictive electromechanical power source and a fuel cell operatively connected to such source.
Fuel cells are well known and are used for a variety of different purposes, including the production of power within a living organism.
Thus, by way of illustration, U.S. Pat. No. 3,837,922 issued in 1974 to Daniel Ng et al. This patent claimed a fuel cell adapted to be implanted in a body having an anode and an air-breathing cathode for producing electrical energy as derived from blood and air flowing through said fuel cell and supplying said electricity to a prosthetic device implanted in a human body. The fuel cell of this patent comprises: (a) a fuel cell housing adapted for implantation into said human body; (b) a first sinusoidal cell unit disposed in said housing comprising: i. a cathode assembly for receiving air comprising a catalytic cathode material applied to a support membrane, said support positioned in said housing to define a plurality of interconnected U-shaped cathode chambers said support having a relatively sinusoidal folded configuration and adapted to receive air in the interior of said U-shape; ii. said cathode support membrane being adapted to transfer ions between the anode and cathode; iii. a second membrane disposed in said housing positioned a spaced apart parallel distance from the sinusoidal cathode support to define an anolyte chamber therebetween; iv. an anode catalyst positioned in said anolyte chamber to define an anode; v. said second membrane adapted to separate a blood ultrafiltrate containing reactive organic compounds from whole blood and to transfer said reactive organic compounds into association with said anode; (c) a second sinusoidal cell unit disposed in said housing, of identical construction as the first cell unit, the second membrane of the second cell unit being positioned a parallel spaced apart distance from the second membrane of the first cell unit to define a blood chamber between said second membrane; (d) a conduit for transfer of air from the exterior of said body to said cathode chambers, said conduit adapted to be implanted in said body and having an opening communicating with the exterior of the body; (e) means for current collection from said anode and cathode to provide electrical current for said prosthetic device; f) means for connecting the first and second sinusoidal cell units electrically together in series or parallel, to provide a predetermined cell voltage and current output value range; (g) means for transfer of blood to said blood chamber; (h)said first cell and second cell positioned in said housing to provide blood and air flow through said blood chamber and cathode chamber. The entire disclosure of this United States patent, and of related U.S. Pat. No. 3,879,922, is hereby incorporated by reference into this specification.
By way of further illustration, in 1975 U.S. Pat. No. 3,861,397 issued to Raghavendra Rao et al. This patent claimed an implantable fuel cell, particularly for operating heart beat actuators, artificial hearts and the like, said cell in operational condition utilizing an oxidizable body substance, preferably glucose as fuel, and oxygen from the body fluids, said cell comprising an enclosure impermeable to body fluids, a fuel electrode means, at least one porous oxygen electrode means selectively reacting oxygen in the presence of fuel, said electrode means located in said enclosure and including associated electrical connection means for deriving electrical energy from the cell under the condition of operation, hydrophilic means which are non-permeable to proteinous substance, blood corpuscles, etc., spacing said electrode means from each other and said enclosure and means in said enclosure for guiding the diffusing operational mixture of fuel and oxygen first to said selective oxygen electrode means and there through to said fuel electrode means. The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification.
By way of further illustration, in 1981 U.S. Pat. No. 4,294,891 issued to Shang J. Yao. This patent claimed a biologically acceptable, implantable, bio-oxidant fuel cell comprising in operative combination: (a) at least one anode assembly; (b) at least one cathode assembly; (c) a fuel/electrolyte chamber defined between said anode and said cathode assemblies for receiving an externally supplied fuel; (d) an electrical lead attached to each of said anode and cathode assembly to provide electrical output to a prosthesis; (e) a biologically acceptable, oxygen permeable membrane disposed substantially in contact with said cathode assembly so that said membrane lies between said cathode and body tissue, said membrane being adapted to permit endogenous tissue oxygen as a biological oxidant to diffuse into said cell from said body tissue; a (f) fuel/electrolyte composition disposed in said fuel/electrolyte chamber; and (g) said fuel/electrolyte composition having a high concentration ratio of fuel to endogenous tissue oxygen diffusing through said membrane into said cell. The entire disclosure of this United States patent is hereby incorporated by reference into this specification.
Thus, fuel cells which are implantable into a living organism have been known since at least as early as 1974. These prior art implantable fuel cells either utilized oxygen and hydrogen naturally present within the living organism and/or they produced some or all of the oxygen and/or hydrogen from electrolysis of bodily fluid. The prior art did not disclose effective means for powering the electrolysis reactions. Furthermore, the membrane technology used to separate the hydrogen and oxygen from each other was not well developed. Additionally, the fuel cell membrane, which also could be used to separate the oxygen and hydrogen from each other, was not effective.
In a book by Karl Kordesch et al., entitled xe2x80x9cFuel Cells and Their Applicationsxe2x80x9d (VCH Verlagsgesellschaft mbH, Weinheim, Germany, 1996), it was disclosed at page 74 that xe2x80x9c. . . progress in this technology was slow due to the xe2x80x98drying outxe2x80x99 of the membrane during operation of the system. The major problem with the General Electric fuel cell was keeping the membrane wet under operating conditions.xe2x80x9d
To the best of applicant""s knowledge, the implantable fuel cells described in the patents discussed above never have been commercially available.
It is thus an object of this invention to provide a fuel cell assembly which durably and reliably produces electric power and which does not decline in performance with age.
In accordance with this invention, there is provided a fuel cell assembly comprised of a electrostrictive means for generating an electrical current, means for utilizing said electrical current to electrolyze water and produce oxygen and hydrogen, and fuel cell means for converting said oxygen and hydrogen into electrical energy.